1. (Field of the Invention)
The present invention relates a piezo-electric vibrator pump in which suction and discharge of fluid are accomplished by the vibration of a piezo-electric vibrator formed of a piezo-electric film of a monolayer or laminate, and more particularly to a piezo-electric vibrator and a piezo-electric vibrator with an invertor of high efficiency suction non-return valve can be operated promptly according to the vibration generated by the frequency voltage produced when it is driven by an alternate current supply.
2. (Description of the Prior Art)
Referring to the usual piezo-electric vibrator pump shown in FIG. 5, the usual piezo-electric pump comprises a piezo-electric vibrator 2 mounted in a casing 1 having a peripheral part secured to casing 1 within casing 1. The piezo-electric vibrator 2 is formed of two laminated piezo-electric layers 9, 9 and electrode 3 inserted between the two piezo-electric layers 9, 9, and electrodes 4, 4 laminated on both sides of laminated two piezo-electric layers 9, 9. Lead wires 11, 12 are connected to the electrodes 3, 4. The piezo-electric vibrator pump is provided with a suction non-return valve 5 (check valve) and a discharge non-return valve 6. An alternate current voltage e is applied between the electrodes 3, 4 of said piezo-electric vibrator 2 through lead wires 11, 12 which results in vibration of said piezo-electric vibrator causing fluid to be sucked through the suction non-return valve 5 and discharged through the discharge non-return valve 6 with the vibration of the piezo-electric vibrator.
However, because of direct attachment of the piezo-electric vibrator 2 to the casing, the usual pump has many disadvantages. The vibration of the piezo-electric vibrator 2 is restricted so that the amplitude of the piezo-electric vibrator 2 becomes smaller, its performance is lower, its insulation characteristic is inferior, noise occurs due to the vibration of the piezo-electric vibrator, and in some cases stresses are imposed on the parts of the piezo-electric vibrator attached to the casing to such an extent that the piezo-electric vibrator may be broken.
Further, in the usual construction of a piezo-electric vibrator not coated with an elastic layer, piezo-electric vibrator 2, secured to a pump casing 1, is vibrated as shown in FIG. 5. That is, there is a scarcely displaced part at the peripheral part of the piezo-electric vibrator so that a dead space is formed, resulting in lower gas suction-discharge capability and lower liquid selfsuction. In order to remove such a dead space, it is conceived to lessen the clearance between the piezo-electric vibrator 2 and an inner surface of the casing 1. However, there is the possibility that the collision of the piezo-electric vibrator with the casing 1 can occur resulting in the breakdown of the piezo-electric vibrator.